He ruled that it is permissible (“ḥalāl”) for Shi’i Muslims to use such substances, provided it be under the direction and supervision of qualified experts. He also ruled that such plant substances as a rule do not impair the mind.

There are no exact specifications in Grand Ayatollah Rohani’s fatwa as to which entheogens and psychoactive substances are meant to be included in the ruling and which ones are deemed to be excluded.

However detailed discussions over 18 months with the Ayatollah leading up to his ruling included the effects and properties of DMT, Ayahuasca and Haoma, psilocybin mushrooms, cannabis, LSD and Ibogaine.

The full story of how this all came about is revealed in an interview with Wahid Azal, a Sufi mystic and Islamic scholar. He explains how formal discussions regarding the use of these drugs were initiated at the highest level’s of the orthodox Shi’i ecclesiastical establishment in Iran.

One of the reasons for this enlightened attitude could be due to psychedelics resemblance to psycho active harmaline which is found in the sacred plant Esfand (peganum harmala), which the Prophet himself took for 50 days at one point (according to one variant of the Faith).

This ruling could have have reaching implications as it will allow medical research into psychedelics to proceed in important parts of the Muslim world; research which is either banned or does not receive the financial support it deserves in the west.